15 Warning Messages 中文.md

[TOC]

15 警告消息

15.1 引言

During compilation, SWIG may generate a variety of warning messages. For example:

在编译期间，SWIG 可能会生成各种警告消息。例如：

example.i:16: Warning 501: Overloaded declaration ignored.  bar(double)
example.i:15: Warning 501: Previous declaration is bar(int)

Typically, warning messages indicate non-fatal problems with the input where the generated wrapper code will probably compile, but it may not work like you expect.

通常，警告消息指示输入可能发生的非致命问题，生成的包装程序代码可能会通过编译，但可能无法按预期工作。

15.2 警告消息抑制

All warning messages have a numeric code that is shown in the warning message itself. To suppress the printing of a warning message, a number of techniques can be used. First, you can run SWIG with the -wcommand line option. For example:

所有警告消息都有一个数字代码，显示在警告消息本身中。可以使用多种技术禁止打印警告消息。首先，你可以使用 -w 命令行选项运行 SWIG。例如：

% swig -python -w501 example.i
% swig -python -w501,505,401 example.i

Alternatively, warnings can be suppressed by inserting a special preprocessor pragma into the input file:

或者，可以通过在输入文件中插入特殊的预处理器编译指令来抑制警告：

%module example
#pragma SWIG nowarn=501
#pragma SWIG nowarn=501,505,401

Finally, code-generation warnings can be disabled on a declaration by declaration basis using the %warnfilter directive. For example:

最后，可以使用 %warnfilter 指令在逐个声明的基础上禁用代码生成警告。例如：

%module example
%warnfilter(501) foo;
...
int foo(int);
int foo(double);              // Silently ignored.

The %warnfilter directive has the same semantics as other declaration modifiers like %rename, %ignoreand %feature, see the %feature directive section. For example, if you wanted to suppress a warning for a method in a class hierarchy, you could do this:

%warnfilter 指令与其他声明修饰符（如 %rename、%ignore 和 %feature）具有相同的语义，请参见 %feature 指令部分。例如，如果你想取消对类层次结构中方法的警告，则可以执行以下操作：

%warnfilter(501) Object::foo;
class Object {
public:
  int foo(int);
  int foo(double);      // Silently ignored
  ...
};

class Derived : public Object {
public:
  int foo(int);
  int foo(double);      // Silently ignored
  ...
};

Warnings can be suppressed for an entire class by supplying a class name. For example:

通过提供类名称，可以抑制整个类的警告。例如：

%warnfilter(501) Object;

class Object {
public:
  ...                      // All 501 warnings ignored in class
};

There is no option to suppress all SWIG warning messages. The warning messages are there for a reason---to tell you that something may be broken in your interface. Ignore the warning messages at your own peril.

没有禁止所有 SWIG 警告消息的选项。出现警告消息是有原因的——告诉你接口中的某些内容可能“损坏”。忽略警告消息，后果自负。

15.3 开启警告

Some warning messages are disabled by default and are generated only to provide additional diagnostics. These warnings can be turned on using the -Wextra option. For example:

默认情况下，某些警告消息是禁用的，并且仅用于提供其他诊断信息而生成。可以使用 -Wextra 选项打开这些警告。例如：

% swig -Wextra -python example.i

To selectively turn on extra warning messages, you can use the directives and options in the previous section--simply add a "+" to all warning numbers. For example:

要有选择地打开其他警告消息，可以使用上一节中的指令和选项——只需在所有警告编号上添加一个 + 即可。例如：

% swig -w+309,+452 example.i

or in your interface file use either

或者，在你的接口文件中使用

#pragma SWIG nowarn=+309,+452

or

再或

%warnfilter(+309,+452) foo;

Note: selective enabling of warnings with %warnfilter overrides any global settings you might have made using -w or #pragma.

You can of course also enable all warnings and suppress a select few, for example:

注意：使用 %warnfilter 选择性启用警告会覆盖你可能使用 -w 或 #pragma 进行的所有全局设置。

当然，你也可以启用所有警告，并选择关闭某些警告，例如：

% swig -Wextra -w309,452 example.i

The warnings on the right take precedence over the warnings on the left, so in the above example -Wextraadds numerous warnings including 452, but then -w309,452 overrides this and so 452 is suppressesed.

If you would like all warnings to appear, regardless of the warning filters used, then use the -Wall option. The -Wall option also turns on the extra warnings that -Wextra adds, however, it is subtely different. When -Wall is used, it also disables all other warning filters, that is, any warnings suppressed or added in %warnfilter, #pragma SWIG nowarn or the -w option.

右边的警告优先于左边的警告，因此在上面的示例中，-Wextra 添加了很多警告，包括 452，但随后 -w309,452 覆盖了该警告，因此 452 被禁止。

如果你希望所有警告都出现，无论使用什么警告过滤器，请使用 -Wall 选项。-Wall 选项还打开了 -Wextra 添加的额外警告，但是它完全不同。当使用 -Wall 时，它也会禁用所有其他警告过滤器，即在 %warnfilter，#pragma SWIG nowarn 或 -w 选项中禁止或添加的任何警告。

15.4 发出警告消息

Warning messages can be issued from an interface file using a number of directives. The %warn directive is the most simple:

可以使用许多指令从接口文件中发出警告消息。%warn 指令是最简单的：

%warn "900:This is your last warning!"

All warning messages are optionally prefixed by the warning number to use. If you are generating your own warnings, make sure you don't use numbers defined in the table at the end of this section.

The %ignorewarn directive is the same as %ignore except that it issues a warning message whenever a matching declaration is found. For example:

所有警告消息都可以选择以警告编号作为前缀。如果要生成自己的警告，请确保不要使用本节末尾表中定义的数字。

%ignorewarn 指令与 %ignore 指令相同，不同之处在于，只要找到匹配的声明，它就会发出警告消息。例如：

%ignorewarn("362:operator= ignored") operator=;

Warning messages can be associated with typemaps using the warning attribute of a typemap declaration. For example:

可以使用类型映射声明的 warning 属性将警告消息与类型映射关联。例如：

%typemap(in, warning="901:You are really going to regret this usage of $1_type $1_name") blah * {
  ...
}

In this case, the warning message will be printed whenever the typemap is actually used and the special variables will be expanded as appropriate, for example:

在这种情况下，每当实际使用类型映射表时，就会显示警告消息，并且将适当地扩展特殊变量，例如：

example.i:23: Warning 901: You are really going to regret this usage of blah * self
example.i:24: Warning 901: You are really going to regret this usage of blah * stuff

15.5 象征符号

The swigwarn.swg file that is installed with SWIG contains symbol constants that could also be used in %warnfilter and #pragma SWIG nowarn. For example this file contains the following line:

随 SWIG 一起安装的 swigwarn.swg 文件包含符号常量，这些常量也可以在 %warnfilter 和 #pragma SWIG nowarn 中使用。例如，此文件包含以下行：

%define SWIGWARN_TYPE_UNDEFINED_CLASS 401 %enddef

so SWIGWARN_TYPE_UNDEFINED_CLASS could be used instead of 401, for example:

所以 SWIGWARN_TYPE_UNDEFINED_CLASS 可以代替 401，例如：

#pragma SWIG nowarn=SWIGWARN_TYPE_UNDEFINED_CLASS

or

或者

%warnfilter(SWIGWARN_TYPE_UNDEFINED_CLASS) Foo;

15.6 说明

The ability to suppress warning messages is really only provided for advanced users and is not recommended in normal use. You are advised to modify your interface to fix the problems highlighted by the warnings wherever possible instead of suppressing warnings.

Certain types of SWIG problems are errors. These usually arise due to parsing errors (bad syntax) or semantic problems for which there is no obvious recovery. There is no mechanism for suppressing error messages.

抑制警告消息的功能实际上仅提供给高级用户，在正常使用中不建议使用。建议你尽可能修改接口文件以解决警告突出显示的问题，而不是抑制警告。

某些类型的 SWIG 问题是错误。这些通常是由于解析错误（语法错误）或语义问题（无法明显恢复）引起的。没有抑制错误消息的机制。

15.7 将警告视为错误

Warnings can be handled as errors by using the -Werror command line option. This will cause SWIG to exit with a non successful exit code if a warning is encountered.

通过使用 -Werror 命令行选项，可以将警告视为错误。如果遇到警告，这将导致 SWIG 以非成功的退出代码退出。

15.8 消息输出格式

The output format for both warnings and errors can be selected for integration with your favourite IDE/editor. Editors and IDEs can usually parse error messages and if in the appropriate format will easily take you directly to the source of the error. The standard format is used by default except on Windows where the Microsoft format is used by default. These can be overridden using command line options, for example:

可以选择警告和错误的输出格式，以与你喜欢的 IDE 或编辑器集成。编辑器和 IDE 通常可以解析错误消息，并且如果采用适当的格式，则可以轻松地直接将你带到错误源。默认使用标准格式，但在 Windows 上默认使用 Microsoft 格式。这些可以使用命令行选项覆盖，例如：

$ swig -python -Fstandard example.i
example.i:4: Syntax error in input(1).
$ swig -python -Fmicrosoft example.i
example.i(4) : Syntax error in input(1).

15.9 警告代码目录

15.9.1 弃用的功能 (100-199)

• 101. Deprecated %extern directive.
• 102. Deprecated %val directive.
• 103. Deprecated %out directive.
• 104. Deprecated %disabledoc directive.
• 105. Deprecated %enabledoc directive.
• 106. Deprecated %doconly directive.
• 107. Deprecated %style directive.
• 108. Deprecated %localstyle directive.
• 109. Deprecated %title directive.
• 110. Deprecated %section directive.
• 111. Deprecated %subsection directive.
• 112. Deprecated %subsubsection directive.
• 113. Deprecated %addmethods directive.
• 114. Deprecated %readonly directive.
• 115. Deprecated %readwrite directive.
• 116. Deprecated %except directive.
• 117. Deprecated %new directive.
• 118. Deprecated %typemap(except).
• 119. Deprecated %typemap(ignore).
• 120. Deprecated command line option (-runtime, -noruntime).
• 121. Deprecated %name directive.
• 126. The nestedworkaround feature is deprecated.

15.9.2 预处理器 (200-299)

• 201. Unable to find filename.
• 202. Could not evaluate expression expr.
• 203. Both includeall and importall are defined: using includeall.
• 204. CPP #warning, warning.
• 205. CPP #error, error.
• 206. Unexpected tokens after #directive directive.

15.9.3 C/C++ 解析器 (300-399)

• 301. class keyword used, but not in C++ mode.
• 302. Identifier name redefined (ignored).
• 303. %extend defined for an undeclared class name.
• 304. Unsupported constant value (ignored).
• 305. Bad constant value (ignored).
• 306. identifier is private in this context.
• 307. Can't set default argument value (ignored)
• 308. Namespace alias name not allowed here. Assuming name
• 309. [private | protected] inheritance ignored.
• 310. Template name was already wrapped as name (ignored)
• 312. Unnamed nested class not currently supported (ignored).
• 313. Unrecognized extern type name (ignored).
• 314. identifier is a lang keyword.
• 315. Nothing known about identifier.
• 316. Repeated %module directive.
• 317. Specialization of non-template name.
• 318. Instantiation of template name is ambiguous, instantiation templ used, instantiation templ ignored.
• 319. No access specifier given for base class name (ignored).
• 320. Explicit template instantiation ignored.
• 321. identifier conflicts with a built-in name.
• 322. Redundant redeclaration of name.
• 323. Recursive scope inheritance of name.
• 324. Named nested template instantiations not supported. Processing as if no name was given to %template().
• 325. Nested kind not currently supported (name ignored).
• 326. Deprecated %extend name used - the kind name name should be used instead of the typedef name name.
• 350. operator new ignored.
• 351. operator delete ignored.
• 352. operator+ ignored.
• 353. operator- ignored.
• 354. operator* ignored.
• 355. operator/ ignored.
• 356. operator% ignored.
• 357. operator^ ignored.
• 358. operator& ignored.
• 359. operator| ignored.
• 360. operator~ ignored.
• 361. operator! ignored.
• 362. operator= ignored.
• 363. operator< ignored.
• 364. operator> ignored.
• 365. operator+= ignored.
• 366. operator-= ignored.
• 367. operator*= ignored.
• 368. operator/= ignored.
• 369. operator%= ignored.
• 370. operator^= ignored.
• 371. operator&= ignored.
• 372. operator|= ignored.
• 373. operator<< ignored.
• 374. operator>>ignored.
• 375. operator<<= ignored.
• 376. operator>>= ignored.
• 377. operator== ignored.
• 378. operator!= ignored.
• 379. operator<= ignored.
• 380. operator>= ignored.
• 381. operator&& ignored.
• 382. operator|| ignored.
• 383. operator++ ignored.
• 384. operator-- ignored.
• 385. operator, ignored.
• 386. operator-<* ignored.
• 387. operator-< ignored.
• 388. operator() ignored.
• 389. operator[] ignored.
• 390. operator+ ignored (unary).
• 391. operator- ignored (unary).
• 392. operator* ignored (unary).
• 393. operator& ignored (unary).
• 394. operator new[] ignored.
• 395. operator delete[] ignored.

15.9.4 类型与类型映射 (400-499)

• 401. Nothing known about class name. Ignored.
• 402. Base class name is incomplete.
• 403. Class name might be abstract.
• 450. Deprecated typemap feature ($source/$target).
• 451. Setting const char * variable may leak memory.
• 452. Reserved
• 453. Can't apply (pattern). No typemaps are defined.
• 460. Unable to use type type as a function argument.
• 461. Unable to use return type type in function name.
• 462. Unable to set variable of type type.
• 463. Unable to read variable of type type.
• 464. Unsupported constant value.
• 465. Unable to handle type type.
• 466. Unsupported variable type type.
• 467. Overloaded declaration not supported (incomplete type checking rule - no precedence level in typecheck typemap for 'type')
• 468. No 'throw' typemap defined for exception type type
• 469. No or improper directorin typemap defined for type
• 470. Thread/reentrant unsafe wrapping, consider returning by value instead.
• 471. Unable to use return type type in director method
• 474. Method method usage of the optimal attribute ignored in the out typemap as the following cannot be used to generate optimal code: code
• 475. Multiple calls to method might be generated due to optimal attribute usage in the out typemap.
• 476. Initialization using std::initializer_list.
• 477. No directorthrows typemap defined for type

15.9.5 代码生成 (500-599)

• 501. Overloaded declaration ignored. decl. Previous declaration is decl.
• 502. Overloaded constructor ignored. decl. Previous declaration is decl.
• 503. Can't wrap identifier unless renamed to a valid identifier.
• 504. Function name must have a return type. Ignored.
• 505. Variable length arguments discarded.
• 506. Can't wrap varargs with keyword arguments enabled.
• 507. Adding native function name not supported (ignored).
• 508. Declaration of name shadows declaration accessible via operator->(), previous declaration of'declaration'.
• 509. Overloaded method declaration effectively ignored, as it is shadowed by declaration.
• 510. Friend function name ignored.
• 511. Can't use keyword arguments with overloaded functions.
• 512. Overloaded method declaration ignored, using non-const method declaration instead.
• 513. Can't generate wrappers for unnamed struct/class.
• 516. Overloaded method declaration ignored, using declaration instead.
• 518. Portability warning: File file1 will be overwritten by file2 on case insensitive filesystems such as Windows' FAT32 and NTFS unless the class/module name is renamed.
• 519. %template() contains no name. Template method ignored: declaration
• 520. Base/Derived class classname1 of classname2 is not similarly marked as a smart pointer.
• 521. Illegal destructor name name. Ignored.
• 522. Use of an illegal constructor name name in %extend is deprecated, the constructor name should be name.
• 523. Use of an illegal destructor name name in %extend is deprecated, the destructor name should be name.

15.9.6 特定语言模块警告 (700-899)

• 801. Wrong name (corrected to name). (Ruby).
• 810. No jni typemap defined for type (Java).
• 811. No jtype typemap defined for type (Java).
• 812. No jstype typemap defined for type (Java).
• 813. Warning for classname, base baseclass ignored. Multiple inheritance is not supported in Java. (Java).
• 815. No javafinalize typemap defined for type (Java).
• 816. No javabody typemap defined for type (Java).
• 817. No javaout typemap defined for type (Java).
• 818. No javain typemap defined for type (Java).
• 819. No javadirectorin typemap defined for type (Java).
• 820. No javadirectorout typemap defined for type (Java).
• 822. Covariant return types not supported in Java. Proxy method will return basetype (Java).
• 823. No javaconstruct typemap defined for type (Java).
• 824. Missing JNI descriptor in directorin typemap defined for type (Java).
• 825. "directorconnect" attribute missing in type "javaconstruct" typemap. (Java).
• 826. The nspace feature is used on type without -package. The generated code may not compile as Java does not support types declared in a named package accessing types declared in an unnamed package. (Java).
• 830. No ctype typemap defined for type (C#).
• 831. No cstype typemap defined for type (C#).
• 832. No cswtype typemap defined for type (C#).
• 833. Warning for classname, base baseclass ignored. Multiple inheritance is not supported in C#. (C#).
• 835. No csfinalize typemap defined for type (C#).
• 836. No csbody typemap defined for type (C#).
• 837. No csout typemap defined for type (C#).
• 838. No csin typemap defined for type (C#).
• 842. Covariant return types not supported in C#. Proxy method will return basetype (C#).
• 843. No csconstruct typemap defined for type (C#).
• 844. C# exception may not be thrown - no $excode or excode attribute in typemap typemap. (C#).
• 845. Unmanaged code contains a call to a SWIG_CSharpSetPendingException method and C# code does not handle pending exceptions via the canthrow attribute. (C#).
• 870. Warning for classname: Base baseclass ignored. Multiple inheritance is not supported in PHP. (Php).
• 871. Unrecognized pragma pragma. (Php).

15.9.7 用户自定义 (900-999)

These numbers can be used by your own application.

这些数字可被你自己的应用程序使用。

15.10 历史

The ability to control warning messages was first added to SWIG-1.3.12.

SWIG-1.3.12 中首次添加控制警告信息的功能。